1. Field of the Invention
The invention relates to devices for milking dairy animals and in particular to devices provided with disinfecting means for supplying disinfecting fluids to parts of the device. The invention further relates to methods of milking dairy animals including the performing of such disinfecting procedures. More particularly it relates to teat cup cleaning devices of the type comprising a heating chamber, provided with a discharge outlet, closable by means of a valve, and arranged for connection to a teat cup for high temperature cleaning.
2. Description of the Related Art
Devices for milking dairy animals are known in which, in the context of disinfection, steam is applied that is sufficiently hot for heating at least a part of a teat liner and/or teat cup to a temperature at which micro-organisms and bacteria are killed or eliminated. The disinfection and/or sterilisation should preferably comprise the whole inner part of a teat liner. The known cleaning methods consist of the steps of: removing milk or other residues that are present on at least the teat liner by means of a cleaning fluid; removing the cleaning fluid, and disinfecting at least a part of the teat liner with steam. Applying both a cleaning fluid and a disinfecting fluid for cleaning, respectively disinfecting a teat liner implies a relatively large consumption of fluids and energy.
Such a device and method of milking a dairy animal are known for instance from PCT patent application WO 03/077645. According to one embodiment of WO 03/077645 there is provided a chamber which is closable by means of a pressure-controlled valve and which is provided with heating means. The valve opens at a selected overpressure, and remains open until the pressure has dropped to about atmospheric pressure. In this manner a puff or blow of vapor may be obtained. A water tank provides a constant flow velocity of water to the chamber via a non-return valve. A drawback of the known device is that even a strong steam jet has a limited cleaning/disinfecting power, often insufficient for cleaning and/or disinfecting a teat cup in a reliable manner. Furthermore, the known device is unable to supply water to the teat cup while the chamber is being heated to produce steam. There is thus a particular need for a device and method providing a more reliable cleaning and/or disinfecting action. It would be furthermore desirable to provide a device in which water could be supplied to the teat cup even during steam preparation.